Hi OBLIGED1,
It sounds like you've isolated the printing issue to the Gmail app. For help with the feature, be sure the app is fully updated as well. If needed, the steps below found in the article here will assist. How to manually update apps on your Apple device
"How to manually update apps on your iPhone or iPad
- Open the App Store.
- Tap your profile icon at the top of the screen.
- Scroll to see pending updates and release notes. Tap Update next to an app to update only that app, or tap Update All.
"
Additionally, you can view information from the Google support page here: Print Gmail messages, and find helpful information here: Use AirPrint to print from your iPhone or iPad - Apple Support
It also seems like others have had issues with the Google Mail app and printing from iOS devices, as seen in a previous post here: Can't find the Print option on Gmail for …
For further assistance, reach out to the app developer to report the issue: How to contact an app developer
Cheers.